I love eclipses. Solar are the best and most dramatic, but there is still something quite magical about a total lunar eclipse. The Full Moon fades in brightness and eventually turns a deep red colour.
The second total lunar eclipse of 2011 occurs on 11 December. The Moon will enter the Earth’s shadow at 11:45 pm (Australian Eastern Daylight Saving Time) and be fully red at 1:06 am.
More details at: http://en.wikipedia.org/wiki/December_2011_lunar_eclipse
Most of the time the Sun is quiet, shining in space beaming out light and heat. But every eleven years it gets cranky – covered in dark spots and fiery eruptions. This is a time called solar maximum, or solar max for short.
The Sun, like all stars, is a big ball of plasma – mostly hydrogen and helium. Because the Sun is so big – 100 million times bigger than Earth – it has a lot of gravity. The gravity squeezes the plasma so hard that it gives off heat and light. Scientists call this nuclear fusion.
Twenty years ago, the answer this question was ‘only one that we know’. Most astronomers believed that the Sun was no different to most stars in the universe. So if we had a star with planets and moons – a solar system – than why don’t others.
In 1992, the first planet orbiting another star – sometimes called an exoplanet – was detected. Since then, astronomers have used larger telescopes and faster computers to find more than 450 exoplanets orbiting more than 300 stars.
A busy week for me as I had to fill in some blanks in the schedule. One story was on genes relating to menarche (onset of female puberty) and the other was traces of oxygen found on Saturn’s moon Rhea.
Astronomers measure the distance to other galaxies by looking at their colour. The more red a galaxy is, the faster it is moving from us and the further it is away.
Another way to measure distance is to look at the brightness of exploding stars – called supernova. These explosions are brighter the closer they are to us. By measuring the brightness it is possible to know how far away they, and the galaxy they live in, are from us.
Using these techniques astronomers have seen galaxies more than 13 billion light years away.
Space telescopes that measure cosmic background radiation, which are the remains of the Big Bang explosion. It is thought to be the outer edge of our Universe and is 13.7 billion light years away.
Did you know that you can use an iPhone to explore the night sky?
There are lots of apps available, but two of the best are Planets and Pocket Universe.
Planets is a free app that shows you where the planets are in the sky and when they rise and set. It also has a 3D view of the Earth showing where it is day and night.
Pocket Universe costs A$3.99. It displays maps of the night sky for your location, the position of Jupiter’s moon, lunar calendars and the latest space news.
The best feature of this app is that it can help you identify objects in the sky. At night, hold the iPhone up to the sky and the map will display exactly what you are looking at – no more guess work.
Posted in Blog
Tagged astronomy, iphone
This is a difficult question to answer, because the number keep growing.
Almost every year astronomers find new moons, using better telescopes on Earth and spacecraft flying through the solar systen. Some moons are so small that that their width is smaller than most cities on Earth.
Volcanoes on Earth have rivers of red hot lava pouring down the sides or massive explosions of gas, rock and dust rising into the sky. But in space volcanoes are quite different.
Mars has four large volcanoes – the biggest is Olympus Mons. It is 27 kilometres high (three times the height of Mount Everest) and 500 kilometres wide (bigger than Tasmania). The volcanoes on Mars haven’t erupted for more than two million years.
The planet Venus always has ancient volcanoes on its surface. The biggest is Maat Mons – eight kilometres high. From above, some of the volcanoes look like pancakes and others have strange patterns that make them look like ticks. Continue reading
Astronomers will have to rethink how they measure galaxies, with a new study finding that stars don’t all form the same way.
The research, headed by Dr Gerhardt Meurer of John Hopkins University in Baltimore, appears on the pre-press physics website arxiv.
Read more at ABC Science Online.
A team of astronomers have found the ‘missing link’ of stellar death, revealing what our Sun might look like at the end of its life.
The group of Australian and US astronomers, led by Associate Professor Miroslav Filipovic of the University of Western Sydney, call the new class of object ‘super planetary nebulae’.
They report on their finding in the journal Monthly Notices of the Royal Astronomical Society.
Read the full story on ABC Science Online.